Purification of municipal or industrial waste, silted water or aqueous suspensions of particulate material is complicated by the presence of colloids, slow settling material, industrial waste, variations in the pH, a range of hydrophilic to hydrophobic material and large volumes of effluent. Agents to agglomerate, aggregate, adhere, cohere, congeal, concrete, consolidate, deposit, flocculate, precipitate or dewater the solid material in such waste are known. Early efforts used inorganic salts as such agents but more recently, organic polymers have been employed with success. The active types are thought to exist as a chain of sites to which the suspended solids adhere producing an easily filterable, large mass particle. Some important polymer flocculation or dewaterant agents are described in the following patents: U.S. Pat. No. 3,752,760, U.S. Pat. No. 3,647,769, U.S. Pat. No. 3,300,406, U.S. Pat. No. 3,228,707 and U.S. Pat. No. 3,406,139.
Art recognized flocculating or dewatering agent polymers often have complex, poorly defined structures and are synthesized from a number of ingredients. For example one such polymer is the reaction product of polyacrylonitrile, N,N-dimethyl-1,3-propanediamine and water (U.S. Pat. No. 3,647,769). Others are polymers of 1-vinylimidazoline, 1-vinyltetrahydropyrimidine or N-(methylaminopropyl) acrylamide which are formed by reaction of polyacrylonitrile and ethylenediamine, 1,3-propanediamine, N-methyl-1,3-propanediamine or N-methylpropanediamine respectively in the presence of sulfur (U.S. Pat. No. 3,406,139). In general these agents possess low dewaterant activity compared to the amine polymers of the present invention.